EP3328290B1 - Tool for removing an acetabular ball from an acetabular cup in a hip replacement prosthesis - Google Patents

Tool for removing an acetabular ball from an acetabular cup in a hip replacement prosthesis Download PDF

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Publication number
EP3328290B1
EP3328290B1 EP16831034.0A EP16831034A EP3328290B1 EP 3328290 B1 EP3328290 B1 EP 3328290B1 EP 16831034 A EP16831034 A EP 16831034A EP 3328290 B1 EP3328290 B1 EP 3328290B1
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EP
European Patent Office
Prior art keywords
jaw
tool
shaft
nut
acetabular
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP16831034.0A
Other languages
German (de)
French (fr)
Other versions
EP3328290A4 (en
EP3328290A1 (en
Inventor
Zafer Termanini
Brian Vanhiel
Linda BRADDON
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hip Innovation Technology LLC
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Hip Innovation Technology LLC
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Publication date
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Publication of EP3328290A1 publication Critical patent/EP3328290A1/en
Publication of EP3328290A4 publication Critical patent/EP3328290A4/en
Application granted granted Critical
Publication of EP3328290B1 publication Critical patent/EP3328290B1/en
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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
    • A61F2/4637—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for connecting or disconnecting two parts of a prosthesis
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
    • A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
    • A61B17/88—Osteosynthesis instruments; Methods or means for implanting or extracting internal or external fixation devices
    • A61B17/92—Impactors or extractors, e.g. for removing intramedullary devices
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
    • A61F2/4603—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof
    • A61F2/4609—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof of acetabular cups
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
    • A61B2017/564—Methods for bone or joint treatment
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
    • A61F2/4603—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2002/30001—Additional features of subject-matter classified in A61F2/28, A61F2/30 and subgroups thereof
    • A61F2002/30621—Features concerning the anatomical functioning or articulation of the prosthetic joint
    • A61F2002/30649—Ball-and-socket joints
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2/32—Joints for the hip
    • A61F2/34—Acetabular cups
    • A61F2002/348—Additional features
    • A61F2002/3483—Additional features having a convex shape, e.g. hemispherical heads
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
    • A61F2/4603—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof
    • A61F2002/4619—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof for extraction
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
    • A61F2/4603—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof
    • A61F2002/4625—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof with relative movement between parts of the instrument during use
    • A61F2002/4627—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof with relative movement between parts of the instrument during use with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/30—Joints
    • A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
    • A61F2/4637—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for connecting or disconnecting two parts of a prosthesis
    • A61F2002/4641—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for connecting or disconnecting two parts of a prosthesis for disconnecting

Definitions

  • the present invention relates to surgical tools used in connection with a reverse hip prosthesis. More particularly, the invention has to do with a surgical tool for extracting an acetabular ball from an acetabular cup.
  • a reverse hip prosthesis is described in U.S. Patents Nos. 8,313,531 B2 and 8,540,779 B2 .
  • the prosthesis and a revision surgery method also are described in U.S. Patent No. 8,992,627 B2 .
  • U.S. Patent No. 5,938,701 A discloses an extraction device for removing a socket bearing insert from an acetabular cup in an acetabular prosthesis in which an extracting member is adapted for attachment to a groove in the insert.
  • the acetabular ball is affixed by means of a Morse taper to an acetabular cup stem.
  • the stem extends from the bottom of a concave surface of the acetabular cup.
  • the surgical tool of the invention enables a surgeon to remove the acetabular ball from an implanted prosthesis without pulling on the acetabular cup and without disrupting any bone ingrowth.
  • acetabular ball extractor from time to time to describe the tool of the invention and the term "tool” or “instrument” is sometimes used to refer to either or both of the first and second embodiments of the invention.
  • the tool 1 is the first embodiment of the tool of the invention and is illustrated in perspective in Fig. 1 .
  • the tool 1a is the second embodiment of the tool of the invention and is illustrated in a partially exploded view in Fig. 12 and in elevation in Fig. 2 .
  • the tool 1 comprises a jaw shaft 10 having two or more than two jaws 2 disposed at the distal end thereof. Each jaw 2 is pivotable about a pin 2 having an axis perpendicular to a central axis of jaw shaft 10. And jaw shaft 10 has a threaded proximal end 11. (See Figs. 8 , 12 and 2A .)
  • the jaw shaft 10 is disposed concentrically in outer shaft 4.
  • a bell shaped element, referred to herein as handle bell 3 is affixed to the distal end of outer shaft 4.
  • the handle bell 3 is internally sized to cause jaws 2 to close as the jaws 2 are drawn into the handle bell 3 by proximal movement of jaw shaft 10 toward the proximal end of the tool 1 as explained in more detail below.
  • the handle bell 3 has a circumferential bell edge 33 at its distal end sized to engage a circumferential cup edge 23 of an acetabular cup.
  • Outer shaft 4 has an optional knurled portion 5.
  • a jaw shaft nut 9 or 9a is threaded onto the proximal end of jaw shaft 0 and an outer shaft nut 6 or 6a is affixed to the proximal end of outer shaft 4.
  • the jaw shaft nut abuts the outer shaft nut and the threads at the proximal end of shaft 4 are right handed, tightening jaw shaft nut 9 or 9a by turning it in a clockwise (or right-handed) direction will exert a distal force on nut 6 or 6a causing the jaw shaft 10 to move in a proximal direction relative to the outer shaft 4.
  • the nuts are disposed adjacent to one another with the jaw shaft nut 9 or 9a being disposed proximally to the outer shaft nut 6 or 6a.
  • Jaw shaft 10 is illustrated in section in Figs. 3, 5 and 6 , and in elevation in Fig.8 .
  • Figs. 12 and 12A illustrate the threaded proximal end 1 of jaw shaft 10;
  • Fig. 12A being a magnified view of the proximal end A of the tool illustrated in Fig. 12 .
  • Fig. 7 is an elevation view of outer shaft 4 with an outer shaft nut 6a thereon.
  • the jaw shaft 10 is illustrated in elevation in Fig. 8 with jaws 2 thereon and a block bar 8 is illustrated in elevation in Fig. 9.
  • Figs. 10 and 11 are elevations of handle bell 3 and jaw shaft nut 9a, respectively.
  • the difference between tools 1 and 1a has to do with differences in outer shaft nuts 6 and 6a and jaw shaft nuts 9 and 9a.
  • Nuts 6 and 9 are knurled and holes 7 are provided in the knurled portions to receive block bars 8 which are used to provide leverage in the operation of the tool.
  • Nuts 6a and 9a are also knurled but they are additionally provided with hex portions 14 and 15, respectively.
  • Holes 7a are provided for block bars 8 in hex portions 14 and 15.
  • the hex portions allow the surgeon to use a wrench or wrenches (not shown) instead of some or all of the block bars in order to obtain increased leverage during operation of the tool.
  • flattened portions on the outer surface of the nuts having shapes other than a hex can be used to permit use of a wrench or other tool in order to obtain increased leverage as will be apparent to those having ordinary skill in the art.
  • Figs. 3-6 Also disclosed is the operation of the tool, which operation is illustrated in Figs. 3-6 .
  • the jaws 2 are allowed to open when jaw shaft 10 is pushed in a distal direction while holding shaft 4 so that the jaws move out of handle bell 3.
  • the jaws 2 are hinged by pins 12.
  • Fig. 3 the jaws 2 are shown in section after they have been pushed out of handle bell 3 and pushed over acetabular ball 20.
  • Acetabular ball 20 is securely affixed by means of a Morse taper on stem 21.
  • Stem 21 is affixed to and extends from the concave surface off acetabular cup 22.
  • Figs. 4 and 5 the circumferential bell edge 33 at the distal end of handle bell 3 has been pushed into engagement with the circumferential cup edge 23 of acetabular cup 22.
  • the next step is to grip shaft 4 while turning jaw shaft nut 9 or 9a causing the jaw shaft to move in a proximal direction so that jaws 2 pull on acetabular ball 20 while handle bell 3 exerts an opposing force on the circumferential cup edge 23 of acetabular cup 22.
  • the opposing force prevents pulling on acetabular cup 22 so that the cup is not pulled out of the acetabulum.
  • a rod or block bar 8 is placed in a hole 7 or 7a of outer shaft nut 6 or 6a and another rod or block bar 8 is placed in a hole 7 or 7a of jaw shaft nut 9 or 9a when additional leverage is needed to exert a pulling force on acetabular ball 20 and an opposing pushing force on acetabular cup 22.
  • the holes 7 and 7a are perpendicular to the central axes of the nuts. If more leverage is needed, the block bars 8 are removed from one or both of shaft nuts 6a or 9a and a wrench is used on either or both shaft nuts by placing the open end of the wrench(es) (not shown) over one or both hex portions 14 or 15. When sufficient force is exerted, the ball separates from stem 21 as illustrated by space 30 in Fig. 6 .

Description

    BACKGROUND OF THE INVENTION Field of the Invention
  • The present invention relates to surgical tools used in connection with a reverse hip prosthesis. More particularly, the invention has to do with a surgical tool for extracting an acetabular ball from an acetabular cup.
    • The Related Art
  • A reverse hip prosthesis is described in U.S. Patents Nos. 8,313,531 B2 and 8,540,779 B2 . The prosthesis and a revision surgery method also are described in U.S. Patent No. 8,992,627 B2 .
  • U.S. Patent No. 5,938,701 A discloses an extraction device for removing a socket bearing insert from an acetabular cup in an acetabular prosthesis in which an extracting member is adapted for attachment to a groove in the insert.
    • SUMMARY OF THE INVENTION
  • As described in the patents referenced above, the acetabular ball is affixed by means of a Morse taper to an acetabular cup stem. The stem extends from the bottom of a concave surface of the acetabular cup. The surgical tool of the invention enables a surgeon to remove the acetabular ball from an implanted prosthesis without pulling on the acetabular cup and without disrupting any bone ingrowth. In the present disclosure, we use the term "acetabular ball extractor" from time to time to describe the tool of the invention and the term "tool" or "instrument" is sometimes used to refer to either or both of the first and second embodiments of the invention.
    • Fig. 1 is a perspective view of a first embodiment of the surgical tool of the invention.
    • Fig. 2 is an elevation view of a second embodiment of the tool.
    • Fig. 3 is a section view of the tool in a first step illustrating the jaws positioned over an acetabular ball which has been affixed in an acetabular cup.
    • Fig. 4 is an elevation view of the tool in a second step fully engaged with the acetabular ball and cup.
    • Fig. 5 is a section view of Fig. 4 taken along section line A-A.
    • Fig. 6 is a section view of the tool in a third step illustrating an acetabular ball separated from the stem of the acetabular cup.
    • Fig. 7 is an elevation view of a handle or outer shaft for the acetabular ball extractor.
    • Fig. 8 is an elevation view of a jaw assembly of the acetabular ball extractor.
    • Fig. 9 is an elevation view of a block bar of the acetabular ball extractor.
    • Fig. 10 is an elevation view of the handle bell of the acetabular ball extractor.
    • Fig. 11 is an elevation view of a shaft nut of the second embodiment of the acetabular ball extractor.
    • Fig. 12 is a partially exploded view of the second embodiment of the tool of the invention.
    • Fig. 12A is a magnified view of the proximal end of Fig. 12.
    DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • The tool 1 is the first embodiment of the tool of the invention and is illustrated in perspective in Fig. 1. The tool 1a is the second embodiment of the tool of the invention and is illustrated in a partially exploded view in Fig. 12 and in elevation in Fig. 2.
  • Referring to Figs. 1-6, the tool 1 comprises a jaw shaft 10 having two or more than two jaws 2 disposed at the distal end thereof. Each jaw 2 is pivotable about a pin 2 having an axis perpendicular to a central axis of jaw shaft 10. And jaw shaft 10 has a threaded proximal end 11. (See Figs. 8, 12 and 2A.) The jaw shaft 10 is disposed concentrically in outer shaft 4. A bell shaped element, referred to herein as handle bell 3, is affixed to the distal end of outer shaft 4. The handle bell 3 is internally sized to cause jaws 2 to close as the jaws 2 are drawn into the handle bell 3 by proximal movement of jaw shaft 10 toward the proximal end of the tool 1 as explained in more detail below. The handle bell 3 has a circumferential bell edge 33 at its distal end sized to engage a circumferential cup edge 23 of an acetabular cup. Outer shaft 4 has an optional knurled portion 5.
  • A jaw shaft nut 9 or 9a is threaded onto the proximal end of jaw shaft 0 and an outer shaft nut 6 or 6a is affixed to the proximal end of outer shaft 4. When the jaw shaft nut abuts the outer shaft nut and the threads at the proximal end of shaft 4 are right handed, tightening jaw shaft nut 9 or 9a by turning it in a clockwise (or right-handed) direction will exert a distal force on nut 6 or 6a causing the jaw shaft 10 to move in a proximal direction relative to the outer shaft 4. By way of further explanation, the nuts are disposed adjacent to one another with the jaw shaft nut 9 or 9a being disposed proximally to the outer shaft nut 6 or 6a. Jaw shaft 10 is illustrated in section in Figs. 3, 5 and 6, and in elevation in Fig.8. Figs. 12 and 12A illustrate the threaded proximal end 1 of jaw shaft 10; Fig. 12A being a magnified view of the proximal end A of the tool illustrated in Fig. 12. Fig. 7 is an elevation view of outer shaft 4 with an outer shaft nut 6a thereon. The jaw shaft 10 is illustrated in elevation in Fig. 8 with jaws 2 thereon and a block bar 8 is illustrated in elevation in Fig. 9. Figs. 10 and 11 are elevations of handle bell 3 and jaw shaft nut 9a, respectively.
  • The difference between tools 1 and 1a has to do with differences in outer shaft nuts 6 and 6a and jaw shaft nuts 9 and 9a. Nuts 6 and 9 are knurled and holes 7 are provided in the knurled portions to receive block bars 8 which are used to provide leverage in the operation of the tool. Nuts 6a and 9a are also knurled but they are additionally provided with hex portions 14 and 15, respectively. Holes 7a are provided for block bars 8 in hex portions 14 and 15. The hex portions allow the surgeon to use a wrench or wrenches (not shown) instead of some or all of the block bars in order to obtain increased leverage during operation of the tool. Of course, flattened portions on the outer surface of the nuts having shapes other than a hex can be used to permit use of a wrench or other tool in order to obtain increased leverage as will be apparent to those having ordinary skill in the art.
  • Also disclosed is the operation of the tool, which operation is illustrated in Figs. 3-6. The jaws 2 are allowed to open when jaw shaft 10 is pushed in a distal direction while holding shaft 4 so that the jaws move out of handle bell 3. The jaws 2 are hinged by pins 12. In Fig. 3 the jaws 2 are shown in section after they have been pushed out of handle bell 3 and pushed over acetabular ball 20. Two or more than two jaws may be used as will be apparent to those having skill in the art. Acetabular ball 20 is securely affixed by means of a Morse taper on stem 21. Stem 21 is affixed to and extends from the concave surface off acetabular cup 22.
  • In Figs. 4 and 5 the circumferential bell edge 33 at the distal end of handle bell 3 has been pushed into engagement with the circumferential cup edge 23 of acetabular cup 22. When the tool has been engaged with the ball and cup in this manner, the next step is to grip shaft 4 while turning jaw shaft nut 9 or 9a causing the jaw shaft to move in a proximal direction so that jaws 2 pull on acetabular ball 20 while handle bell 3 exerts an opposing force on the circumferential cup edge 23 of acetabular cup 22. The opposing force prevents pulling on acetabular cup 22 so that the cup is not pulled out of the acetabulum. A rod or block bar 8 is placed in a hole 7 or 7a of outer shaft nut 6 or 6a and another rod or block bar 8 is placed in a hole 7 or 7a of jaw shaft nut 9 or 9a when additional leverage is needed to exert a pulling force on acetabular ball 20 and an opposing pushing force on acetabular cup 22. The holes 7 and 7a are perpendicular to the central axes of the nuts. If more leverage is needed, the block bars 8 are removed from one or both of shaft nuts 6a or 9a and a wrench is used on either or both shaft nuts by placing the open end of the wrench(es) (not shown) over one or both hex portions 14 or 15. When sufficient force is exerted, the ball separates from stem 21 as illustrated by space 30 in Fig. 6.

Claims (5)

  1. A surgical tool (1, 1a) for removing an acetabular ball (20) from an acetabular cup (22) wherein the acetabular ball (20) is affixed by means of a Morse taper to a stem (21) extending from a concave surface of the acetabular cup (22) characterized in that the tool comprises:
    a jaw shaft (10) having two or more than two jaws (2) disposed at a distal end thereof, each jaw (2) being pivotable about an axis perpendicular to a central axis of the jaw shaft (10) and the jaw shaft (10) having a threaded proximal end;
    an outer shaft (4) into which the jaw shaft (10) is concentrically disposed, the outer shaft (4) having a bell shaped element (3) affixed to a distal end thereof, the bell shaped element (3) being open at its distal end and being internally sized to cause the jaws (2) to close when the jaws (2) are drawn into the bell shaped element (3) by proximal movement of the jaw shaft (10) toward a proximal end of the tool (1,1a) and the bell shaped element (3) having a circumferential bell edge (33) at its distal end sized to engage a circumferential cup edge (23) of the acetabular cup (22); and
    a jaw shaft nut (9,9a) threaded onto the proximal end (11) of the jaw shaft (10) wherein tightening of the nut (9,9a) exerts pressure in a distal direction on the proximal end of the outer shaft (4) causing the jaw shaft (10) to move proximally relative to the outer shaft (4) and thereby causing the jaws (2) to exert a pulling force on the acetabular ball (20) while causing the circumferential bell edge (33) of the bell shaped element (3) to exert an opposing force on the circumferential cup edge (23) of the acetabular cup (22) until sufficient tightening of the jaw shaft nut (9,9a) causes the acetabular ball (20) to be released from the stem.
  2. The tool (1,1a) of claim 1 further comprising an outer shaft nut (6,6a) affixed to the proximal end of the outer shaft (4), the jaw shaft nut (9,9a) and the outer shaft nut (6,6a) being disposed adjacent to one another and the jaw shaft nut (9,9a) being disposed proximally to the outer shaft nut (6,6a).
  3. The tool (1,1a of claim 2 wherein the jaw shaft nut (9,9a) and the outer shaft nut (6,6a)each further comprise a hole (7,7a) perpendicular to the central axis thereof, each hole (7,7a) being sized to receive a rod (8) wherein the rod (8) provides leverage for turning the jaw shaft nut (9,9a) relative to the outer shaft nut (6,6a).
  4. The tool (1,1a) of claim 3 wherein one or both of the jaw shaft nut (9,9a) and the outer shaft nut (6,6a) further comprise flattened portions (14,15) on the outer surface thereof to facilitate engagement of a wrench or other tool to provide increased leverage.
  5. A kit containing the surgical tool of claim 1.
EP16831034.0A 2015-07-27 2016-07-15 Tool for removing an acetabular ball from an acetabular cup in a hip replacement prosthesis Active EP3328290B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201562197200P 2015-07-27 2015-07-27
PCT/US2016/042430 WO2017019327A1 (en) 2015-07-27 2016-07-15 Tool and method for removing an acetabular ball from an acetabular cup in a hip replacement prosthesis

Publications (3)

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EP3328290A1 EP3328290A1 (en) 2018-06-06
EP3328290A4 EP3328290A4 (en) 2019-04-03
EP3328290B1 true EP3328290B1 (en) 2020-03-11

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EP16831034.0A Active EP3328290B1 (en) 2015-07-27 2016-07-15 Tool for removing an acetabular ball from an acetabular cup in a hip replacement prosthesis

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EP (1) EP3328290B1 (en)
JP (1) JP6765684B2 (en)
KR (1) KR102376082B1 (en)
CN (1) CN108135587B (en)
AU (1) AU2016298565B2 (en)
BR (1) BR112018001597B1 (en)
CA (1) CA2992583C (en)
ES (1) ES2797749T3 (en)
HK (1) HK1251436A1 (en)
NZ (1) NZ739113A (en)
WO (1) WO2017019327A1 (en)
ZA (1) ZA201800294B (en)

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EP3328290B1 (en) 2015-07-27 2020-03-11 HIP Innovation Technology, LLC Tool for removing an acetabular ball from an acetabular cup in a hip replacement prosthesis
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Publication number Publication date
EP3328290A4 (en) 2019-04-03
EP3328290A1 (en) 2018-06-06
CN108135587A (en) 2018-06-08
BR112018001597B1 (en) 2022-12-06
JP2018526074A (en) 2018-09-13
HK1251436A1 (en) 2019-02-01
JP6765684B2 (en) 2020-10-07
ZA201800294B (en) 2019-09-25
CA2992583C (en) 2023-07-18
KR102376082B1 (en) 2022-03-18
ES2797749T3 (en) 2020-12-03
AU2016298565A1 (en) 2018-02-08
KR20180061142A (en) 2018-06-07
CA2992583A1 (en) 2017-02-02
BR112018001597A2 (en) 2018-09-18
US20190151117A1 (en) 2019-05-23
US10751198B2 (en) 2020-08-25
US11020243B2 (en) 2021-06-01
WO2017019327A1 (en) 2017-02-02
CN108135587B (en) 2021-05-25
US20200337864A1 (en) 2020-10-29
AU2016298565B2 (en) 2020-11-12
NZ739113A (en) 2022-10-28

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